Unique subscriber states for adaptive stream management

ABSTRACT

Consistent with embodiments of the present invention, a system may be provided to provide per-subscriber stream management comprising: a client capable of receiving a playlist containing a subset of segments associated with a video asset; a video application server to request subscriber state information and to build state representations in a subscriber database on a per-subscriber basis; a media segmenter capable of providing the video asset in multiple bit rates; a subscriber state manager capable of managing the current state of one or more subscribers in a subscriber database; and a stream manager capable of requesting the assignment of bandwidth from a wireless infrastructure on a per-subscriber basis.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.13/087,010, filed Apr. 14, 2011, now U.S. Pat. No. 8,861,929, issuedOct. 14, 2014, which is incorporated herein by reference in itsentirety.

TECHNICAL FIELD

The present disclosure relates generally to leveraging the genericdistributed content distribution model using HTTP delivery whileretaining control of the subscriber streaming session.

BACKGROUND

Video streaming has evolved from linear synchronous delivery methods(e.g., RTSP and RTP) to non-linear file delivery methods (e.g., RTMP andHTTP). This transition has disrupted the traditional business models forsuch applications as ad-insertion, access control, and quality ofservice monitoring. New delivery methods, such as progressive-downloadand adaptive bit rate usage have created an environment where the stateof the client is decoupled from the content origin by means of contentdistribution servers. The client may asynchronously request the contentfrom the distribution servers which may mitigate the centralized controlof ad-insertion and quality of service. In addition, the access controlelements may be entrusted to the clients such that they may obtain,decrypt, and decode the content on the distributed servers.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the disclosure can be better understood with referenceto the following drawings. The components in the drawings are notnecessarily to scale. Emphasis is instead placed upon clearlyillustrating the principles of the present disclosure. Moreover, in thedrawings, like references numerals designate corresponding parts throughthe several figures.

FIG. 1 is a block diagram illustrating an example environment in whichcertain embodiments of the present invention may be implemented.

FIG. 2 is a block diagram illustrating an example environment in whichcertain embodiments of the present invention may be implemented.

FIG. 3 is a block diagram illustrating an example environment in whichcertain embodiments of the present invention may be implemented.

FIG. 4 is a block diagram illustrating an example environment in whichcertain embodiments of the present invention may be implemented.

FIG. 5 is a block diagram illustrating an example environment in whichcertain embodiments of the present invention may be implemented.

FIG. 6 is a block diagram illustrating an example environment in whichcertain embodiments of the present invention may be implemented.

FIG. 7 is a block diagram illustrating an example environment in whichcertain embodiments of the present invention may be implemented.

FIG. 8 is a block diagram illustrating an example environment in whichcertain embodiments of the present invention may be implemented.

FIG. 9 is a block diagram illustrating an example environment in whichcertain embodiments of the present invention may be implemented.

FIG. 10 is a block diagram of a system including a network device.

DESCRIPTION OF EXAMPLE EMBODIMENTS

In various embodiments, a method may be provided to provideper-subscriber stream management comprising: receiving a playlistreferencing a sequence of stream segments associated with an asset,wherein the playlist references a set of playlists that referencedifferent bit rates, and wherein the sequence of stream segments is asubset of the entirety of segments associated with the asset; selectingone of the playlists in the set; downloading at least one of thesequence of stream segments in the selected playlist; establishing astate associated with a subscriber requesting the asset, wherein thestate is different than the state for a second subscriber requesting thesame asset; determining whether the rate of delivery is too high or toolow based on network conditions and the subscriber state; and requestinga different one of the playlists referencing a different bit rate thanthe previously selected playlist.

Consistent with embodiments of the present invention, a method may beprovided to provide per-subscriber stream management comprising:providing a catalog of video assets to one of a plurality of requestingsubscribers; receiving a selection of a first video asset; creating astate unique to the requesting subscriber; requesting one or moreplaylists associated with the video stream; creating a data structurelist representing the available stream sequences for each bit rateavailable to the subscriber; and providing the subscriber with adynamically built playlist containing a subset of the entirety ofsegments associated with the video asset at subscriber-eligible bitrates.

Consistent with embodiments of the present invention, a system may beprovided to provide per-subscriber stream management comprising: aclient capable of receiving a playlist containing a subset of segmentsassociated with a video asset; a video application server to requestsubscriber state information and to build state representations in asubscriber database on a per-subscriber basis; a media segmenter capableof providing the video asset in multiple bit rates; a subscriber statemanager capable of managing the current state of one or more subscribersin a subscriber database; and a stream manager capable of requesting theassignment of bandwidth from a wireless infrastructure on aper-subscriber basis.

Embodiments of the present invention may leverage the genericdistributed content distribution model using HTTP delivery whileretaining control of the subscriber's streaming session. Benefits tothis approach include the ability to perform per-subscriberad-insertion, per-subscriber quality of service management, andper-subscriber accounting. In some embodiments, the content creation andpackaging may be conducted by a third party while the service providerconducts the content packaging.

The opportunity for the service provider to perform the contentpackaging may allow monetization through ad-insertion and performinglocal content insertion. For example, pegs and/or barkers may be locallyinserted. Also, the content provider's ability to conduct per-subscriberstate management may allow the provider the opportunity to provision,assign, monitor, and reclaim capacity for an improved quality of viewingexperience.

The HTTP average bitrate (“ABR”) methods as applied in industry, mayrequire a stream encoding server to produce a sequence of MPEG2TS filesthat represent the video asset to be presented to the subscriber. Thevideo asset may be encoded in multiple bit rates such that a variety ofviewing devices may be used while traversing network environments withdiverse bandwidth delivery characteristics. The encoding server maycreate a playlist file formatted as an M3U8 file. This file may directlyreference the sequence of stream segments.

Alternatively, the playlist file may reference a set of playlists thatreference different bit rates. Embodiments of the present invention mayhave the client download the playlist and subsequently download eachstream segment in the playlist. The client may then determine that therate of data delivery for a specific stream is too low or too high, inwhich case the client may call for a different bit rate of the streamusing a different variant of the playlist.

One problem with the above-described approach may be that the client maybe provided the playlist that describes the entire stream sequence for avideo-on-demand and immediately begin downloading the segments as fastas it can. In fact, the client could collect all the segmentssimultaneously using a widely distributed peer-to-peer contentdistribution network. The impact may be a flash demand for contentdownload. In a bandwidth constrained infrastructure such as a 2G/3Gwireless access network, such an event may be disastrous and lead to adenial of service.

As such, embodiments of the present invention may provide the subscriberwith a subset of the stream segments such that the client may be forcedto regulate the segment requests. Such an approach may be naturallyinduced for a HTTP Live Streaming method where the next segments may beautomatically concatenated to the end of the playlist. Assuming theclient has caught up, the client request for the next index file willonly review the next available set of segments. The HTTP Live Streamingmethod may also delete expired streaming segments from the playlistusing a first-in, first-out method. This may allow the maintenance of asliding window to mitigate the client's ability to “start over” andperform a rapid catch up function.

This is not the case for a classic video on demand set up where theentire stream sequence must be persistently available and defined by theplaylist. This may be accomplished only by creating a state for aper-subscriber playlist with a finite set of segments that the serviceprovider deems is reasonable for the client to collect, buffer, andrender. The operator may allow the client access to some historicalsegments in the playlist to facilitate rewind or the client may allow afinite set of segments in the future to allow some fast-forwardcapabilities while minimizing the opportunity for the client to downloadthe entire sequence of streams. The window of available segment may beconfigurable. In the case of HTTP Live Streaming, the window can only beconfigurable for the past segments as the new window segments have notyet been created. However, embodiments of the present invention mayleverage the windowing concept when applied to on-demand streams aswell.

The stream management function of embodiments of the present invention,may require a subscriber to login and view a catalog of video assets.The subscriber may then select a video and create a state on aper-subscriber session. The stream manager may then query the originserver for the playlist associated with the stream(s) and create a datastructure list representing the sequence of stream segments for eachbit-rate. The client may then perform a standard HTTP GET call to thestream manager. The GET call may result in the dynamic building of aplaylist file in the appropriate M3U8 format.

The dynamically created playlist may have a short sequence of streamsegments (e.g. 30 seconds duration) at the subscriber eligible bit rateswith a defined specified expiration time. The client may then interpretthe playlist and begin to download the segments specified in theplaylist. This may be accomplished through standard HTTP GET calls tothe content distribution system. It should be noted that the acquisitionof the playlist (i.e., the control plane) may be a separate call fromthe acquisition of the content (i.e., the data plane).

As the client buffers the video stream, it begins decoding and renderingthe video to the player. In the meantime, the client may recognize thatthe segments prescribed in the playlist is about to be exhausted and maysubsequently query the stream manager for the playlist of the asset. Thestream manager may then dynamically build a new playlist based on theknown state of the client (the last sequence referenced). The streammanager may present the client with the next set of segments in thesequence. As a result, the client may continue to download the streamsegments filling the buffer for linear rendering.

Since each subscriber may be assigned with a unique state in the streammanager each client may have a different reference point into the samemedia files stored on the content distribution system. The mediadelivered can be video-on-demand where each subscriber may be given aunique instance of the playlist. Alternatively, live delivery may beprovided when all subscribers are presented with the same instance of alive playlist. In either case, the content may have a finite lifetime asdefined by the per-subscriber state in the stream manager.

One advantage of embodiments of the present invention is the ability tomonitor the state of the subscriber's session. The state manager mayallow the content provider to perform a number of functions, includingthe managing quality of service on a per-subscriber basis. Furthermore,the content provider may be allowed to perform accounting on aper-subscriber basis, and perform local ad insertion functions.

The stream manager may be cognizant of the available stream bit ratesfor a given asset based on the asset's playlist variants for eachencoding. The media segmenter may produce the asset in multiple bitrates according to the operator or content provider's specifications.The availability of the stream variants associated with the asset may beregulated in embodiments of the present invention. The default case whenconsidering HTTP ABR may be that the playlist itself may contain all ofthe relevant stream variants. For on-demand, the playlist may containall of the variants with all segments from beginning to end.

In embodiments of the present invention, the principle function of thestream manager may be to provide some boundaries on the availability ofthe content such that the delivery process may be optimized to theclient according to policy, available bandwidth, usage limits, andclient state. It should be understood that there may be several optionsavailable for quality of service management.

Again, in a default case, the client may select the highest bit-ratestream and attempt to fill the buffer. The client may detect thedepletion of the video buffer and adapt to a lower stream rate accordingto the network's ability to deliver content in a consistent manner. Inthe case of a wireless infrastructure, the available bandwidth may varyover time according to RF interference, allocation of the default bearerto more clients, and distance attributed to mobility. In this case,embodiments of the present invention may use the stream manager toregulate the rates available to the client and the assigned capacity inthe wireless infrastructure.

The client may select a high bit-rate stream in which the stream managercan make a call to a policy control and rules function (“PCRF”). Anexample is the ability of the stream manger to request the assignment ofbandwidth from the wireless infrastructure for the highest bit-rateavailable in the asset. The PRCF may grant the request, deny therequest, or provide a best option response. The stream manager can usethe result to facilitate optimized streaming to the client at therequested bit-rate. The stream manager may eliminate stream rates of theasset that the network is unable to deliver.

The dynamically created playlist for this subscriber may include only asubset of the available stream rates. The subset still allows the clientto adapt to localized conditions (i.e. lower its bit rate due to CPUissues or increase its bit rate to maximize quality.) Alternatively, thestream manager may reject the client's request. However, this may beconsidered unacceptable since the subscriber has presumably paid for aservice. However, there may be cases where the PCRF is unable to deliverany of the bit-rates available in which case it is better to denyservice to a subscriber than to induce a congested network to the pointof creating a denial of service for all subscribers.

Furthermore, the stream manager may downgrade the clients request byrestricting access to specific playlist variants (e.g. only playlistswith stream rates below 512 kbps are available). This case may conformto a best-effort model (i.e. undefined bit-rate is available) or abest-match model (i.e. 512 kbps of capacity will be assigned to thesubscriber). The stream manager may reserve the bandwidth through thePCRF. Since the stream manager knows the duration of the client's lastplaylist request, the stream manager can expire the subscriber'ssession. In doing so, the current state of the playlist can be saved orarchived. In addition, expired sessions may invoke the stream manager todelete the bandwidth assigned by the PCRF or sustain the bandwidth inanticipation of the client initiating a resume function.

The threshold for expiration, archiving, and decommissioning ofresources can all be configured on a per-subscriber bases in the statemanager function. Finally, the playlist delivered to the client mayinclude the URL of the specific segments available for streaming. Thestream manager may append attributes to the URL that serve as bandwidthhints. The URL for the 512 kbps might have the +512 kbps tag appendedwhile the URL for the 256 kbps segments might have the +256 kbps tagappended. The client may now make a request for the segments from thestream server. A specialized stream server in a CDN can interpret thebandwidth requirement from a client request by noting the bit-rateappended to the URL.

In doing so, the stream server may throttle the deliver delivery rate ofthe stream in accordance with the bit-rate assigned by the PCRF. Thismay allow the stream server to trickle the content at the appropriaterate to the client such that the queue depths in the wirelessinfrastructure are not flooded with oversized HTTP downloads. Instead ofthe attempting to download a 10 second segment of 1 MB instantaneously,the stream server can deliver the 1 MB segment over an extended periodof time such as 2× the bit rate to insure the content is delivered wellin advance of the client's buffer being exhausted, but still allowingthe RF network the ability to handle the stream without overflowing thequeues.

The archival functions in the stream manager may serve as a pseudo‘bookmark’ for resume playing features. A client that has beendisconnected may be presented with the asset list and a resume option.The resume option allows the stream manager to dynamically build a newper-subscriber playlist based on the subscriber's last playlistdownload. The asset may have a time reference marker associated witheach segment.

The time marker may be used to correlate resume functions when usingother linear streaming methods such as RTSP's use of the NPT attribute.

The per-subscriber stream manager may also induce the client to downloadplaylists of ad-inserts, peg/barker messages, or local streams. Thestream manager can dynamically build the playlist with mid-streaminserts and associated call-backs to resume play of the primary asset.The stream manager can also perform the accounting functions based onthe playlist requests. The playlist for the primary asset can be used todetermine roughly how much data has been delivered, the ad-streamspresented, and confirmation of peg/barker announcements.

From an accounting perspective, the stream manager may be used to insertoperator messages to notify the subscriber of threshold limits that areoccasionally used on wireless access services. Threshold limits mightinclude service expiration times or data delivery limits. These operatordefined playlists may be used to redirect the client to an accountingfunction (e.g. credit card billing) to extend the time threshold orincrease the data delivery limits. The relationships between the client,the origin server, and the distribution servers are controlled by thestream manager. Although the stream manager serves as an intermediarybetween the client and the origin/content distribution servers withrespect to the control plane, the traditional content distributionfunctions such as HTTP can still be used for data plane distributionbetween the client and the content server.

The content distribution system may simply serve as a caching HTTPserver on behalf of the origin server. Essentially, the stream managerbriefly relinquishes control of the stream download between the clientand the content distribution system while forcing the client to‘periodically check in’ to maintain the download. The rate that theclient is required to ‘check in’ is a function of stream manager'spolicy. The stream manager may specify that the client can download thestream based on an increment of the smallest atomic unit (i.e. a singlesegment) up to the complete stream where the end-of-stream marker isread. The latter case might be used for short clips (e.g. 3 to 5minutes) where state management is less relevant while the former casewould be used for assets such as full length feature films.

Embodiments of the present invention for stream management may beimplemented in hardware, software, firmware, or a combination thereof(collectively or individually also referred to herein as logic). To theextent certain embodiments, or portions thereof, are implemented insoftware or firmware, executable instructions or code for performing oneor more tasks of per-subscriber stream management are stored in memoryor any other suitable computer readable medium and executed by asuitable instruction execution system. In the context of this document,a computer readable medium is an electronic, magnetic, optical, or otherphysical device or means that can contain or store a computer programfor use by or in connection with a computer related system or method.

To the extent embodiments, or portions thereof, are implemented inhardware, the present invention may be implemented with any or acombination of the following technologies: a discrete logic circuit(s)having logic gates for implementing logic functions upon data signals,an application specific integrated circuit (ASIC) having appropriatecombinational logic gates, programmable hardware such as a programmablegate array(s) (PGA), a field programmable gate array (FPGA), etc.

FIG. 1 is a block diagram illustrating a network environment in whichcertain embodiments of per-subscriber stream management may beimplemented. Network environment may comprise, for example, a client105. Client 105 may authenticate with a client portal 110. Client 105may include a request to see the playlist 210. Client portal 110 mayquery a subscriber database 115 with a get service request 220 todetermine the assets the subscriber is permitted to view. In someembodiments of the present invention, the request may be based on aservice package associated with client 105. A service package mayconsist of a plurality of assets.

Subscriber database 115 may then send a get asset list request 230 to anasset database 120. Asset database 120 may load assets 240 from anorigin server 130. Asset database may subsequently provide the list ofassets to subscriber database 115 through message 250. The list ofassets includes a plurality of assets associated with the servicepackage. Subscriber database 115 may add catalog options to the assetlist and provide an enhanced catalog message 260 to client portal 110.Client portal 110 subsequently may provide a catalog message 270 toclient 105. Catalog message 270 provides client 105 with a list ofviewable assets associated with their service package.

Turning to FIG. 2, client 105 may now request to play a selection fromthe received catalog. This may be accomplished through a play selectionmessage 310 sent to a video application server 135. Video applicationserver 135 may build a state representation of the subscriber'sactivity. Video application server 135 may send a get asset playlistmessage 320 to asset database 120 to obtain a list of stream options.Asset database 120 may return an asset playlist message 330 to videoapplication server 135. Asset playlist message 320 may comprise aplaylist in m3u8 format which contains all of the stream options for theselected asset.

Video application server 135 may parse the playlist and build a liststructure for the subscriber. The list structure may indicate the offsetinto the featured asset that the subscriber is currently viewing. If theasset has been previously viewed, video application server 135 may senda get subscriber state message 340 to subscriber database 115. Inresponse, subscriber database 115 provides a subscriber state message350 which may contain the last segment delivered to client 105.

Turning to FIG. 3, video application server 135 may now see thatmultiple instances of the asset exist, such as asset playlist 410 andasset playlist 420, which are different instances of the “Avatar” asset.Video application server 135 may then make a capacity request 430 toPCRF 140 through network access 145 at the highest bandwidth available(i.e., 512 kbps). PCRF 140 may subsequently respond with either anacknowledgement message 440 or a rejection message (not shown). At thispoint, PCRF 140 may accept the bandwidth request, which may lead tovideo application server 135 to include the highest bandwidth asset.

FIG. 4 illustrates that video application server 135 may provide thesubscriber playlist message 505 to client 105. Playlist message 505 maycomprise various bandwidth options for client 105 such as asset playlist501 and asset playlist 502. It should be understood that videoapplication server 135 may have only delivered a partial sequence ofsegments associated with the asset. The number of segments may beconfigurable based on the lead time that video application server 135wants client 105 to have available for fast-forward purposes. Client 105may now request each segment of the asset sequentially from thestreamer/cache. For example, client 105 may request and receive asset(avatar512-1.ts) through a series 515 of requests travelling betweenclient 105 and origin server 130. Likewise, client 105 may request andreceive asset (avatar512-2.ts) through a series 525 of requeststravelling between client 105 and origin server 130. Client 105 may havethe option of requesting a lower bit-rate version if the renderingcapabilities of the device are incapable of playing the higher bit-rateversion.

In FIG. 5, client 105 may realize that its buffer has been depleted forthe purpose of rendering and may make a playlist update request 610 tovideo application server 135 before it reached the End of Stream.Playlist update request 610 may be issued to video application server135 which recognizes that client 105 has already requested the previoussegments. Video application server 135 may now send a post client statemessage 620 to subscriber database 115. This will result in the postingof client's 105 state to subscriber database 115. Subscriber database115 may create a representative bookmark 590 for how much of the assetclient 105 has rendered.

Subsequently, subscriber database 115 may respond with a message 630indicating successful update of the current state 590 of the subscriber.Video application server 135 may then send an update request to aservice router 160. Service router 160 may send a response message 650which may indicate the location of any of the requested asset segments.Response message 650 may also indicate the URI (URL?) indicating themost appropriate streamer/cache for client 105 to request the segments.

Turning to FIG. 6, video application server 135 may now refresh therequirement for the highest bit-rate asset available from PCRF 140.Alternatively, PCRF 140 may have asynchronously downgraded the availablebit-rate. Video application server 135 may now know that only a subsetof the streams identified in the playlist 410 may be reliably delivered.As such, the video application server 135 may make a capacity request710 to PCRF 140 through network access 145 at the highest bandwidthavailable (i.e., 512 kbps). PCRF 140 may subsequently respond with anacknowledgement message 720 indicated that the lower bit-rate asset isbeing provided.

Continuing in FIG. 7, video application server 135 may provide client105 with a subscriber playlist message 810 containing subscriberplaylist 840. Subscriber playlist 840 may only offer the lower bit-ratestream to client 105. Again, substitute playlist 840 may be truncatedsuch that client 105 may only render a designated amount of the assetbefore being forced to refresh its playlist. Client 105 may now requesteach segment of the asset sequentially to re-fill the video renderingbuffer. For example, client 105 may request and receive asset(avatar256-3.ts) through a series 820 of requests travelling betweenclient 105 and origin server 130. Likewise, client 105 may request andreceive asset (avatar256-4.ts) through a series 830 of requeststravelling between client 105 and origin server 130.

As client 105 has not reached the end of stream marker in the playlist,client 105 may continue to request the updated playlist 940 asillustrated in FIG. 8. Client 105 sends a request playlist message 905to video application server 135. Video application server 135 sends apost subscriber state message 910 to subscriber database 115. The postedsubscriber state 930 indicates that client 105 has reached the end ofstream marker. This posted subscriber state 930 is delivered via message915 to video application server 135. Subsequently, video applicationserver 135 may deliver playlist 940 to client 105 in playlist message920. Playlist 940 may indicate that the subscriber has now reached endof the stream. Playlist 940 may now include an end of stream indication.Playlist 940 may now further include ant post-roll playlist such asadvertisements or trailers.

Finally, turning to FIG. 9, video application server 135 may indicate toPCRF 140 through message 1010 that the allocated resources may now bereleased since the client stream has completed. The video bearer channelmay then be released by PCRF 140. PCRF 140 may subsequently notify videoapplication server 135 through acknowledgement message 1020 thatnotifies that the state has been removed for client 105.

FIG. 10 is a block diagram of a system including network device 1000.Consistent with embodiments of per-subscriber stream management, theaforementioned memory storage and processing unit may be implemented ina network device, such as network device 1000 of FIG. 10. Any suitablecombination of hardware, software, or firmware may be used to implementthe memory storage and processing unit. For example, the memory storageand processing unit may be implemented with network device 1000 or anyof other network devices 1018, in combination with network device 1000.The aforementioned system, device, and processors are examples and othersystems, devices, and processors may comprise the aforementioned memorystorage and processing unit, consistent with embodiments ofper-subscriber stream management. Furthermore, network device 1000 maycomprise an operating environment for system 100 as described above.System 100 may operate in other environments and is not limited tonetwork device 1000.

With reference to FIG. 10, a system consistent with embodiments of thepresent invention of per-subscriber stream management may include anetwork device, such as network device 1000. In a basic configuration,network device 1000 may include at least one processing unit 1002, asecure processing unit for decryption 1020, and a system memory 1004.Depending on the configuration and type of network device, system memory1004 may comprise, but is not limited to, volatile (e.g., random accessmemory (RAM)), non-volatile (e.g., read-only memory (ROM)), flashmemory, or any combination. System memory 1004 may include operatingsystem 1005, one or more programming modules 1006, and may includeprogram data 1007. Operating system 1005, for example, may be suitablefor controlling network device 1000's operation. Furthermore,embodiments of per-subscriber stream management may be practiced inconjunction with a graphics library, other operating systems, or anyother application program and is not limited to any particularapplication or system. This basic configuration is illustrated in FIG.10 by those components within a dashed line 1008.

Network device 1000 may have additional features or functionality. Forexample, network device 1000 may also include additional data storagedevices (removable and/or non-removable) such as, for example, magneticdisks, optical disks, or tape. Such additional storage is illustrated inFIG. 10 by a removable storage 1009 and a non-removable storage 1010.Computer storage media may include volatile and nonvolatile, removableand non-removable media implemented in any method or technology forstorage of information, such as computer readable instructions, datastructures, program modules, or other data. System memory 1004,removable storage 1009, and non-removable storage 1010 are all computerstorage media examples (i.e., memory storage.) Computer storage mediamay include, but is not limited to, RAM, ROM, electrically erasableread-only memory (EEPROM), flash memory or other memory technology,CD-ROM, digital versatile disks (DVD) or other optical storage, magneticcassettes, magnetic tape, magnetic disk storage or other magneticstorage devices, or any other medium which can be used to storeinformation and which can be accessed by network device 1000. Any suchcomputer storage media may be part of device 1000. Network device 1000may also have input device(s) 1012 such as a keyboard, a mouse, a pen, asound input device, a touch input device, etc. Output device(s) 1014such as a display, speakers, a printer, etc. may also be included. Theaforementioned devices are examples and others may be used.

Network device 1000 may also contain a communication connection 1016that may allow device 1000 to communicate with other network devices1018, such as over a network in a distributed network environment, forexample, an intranet or the Internet. Communication connection 1016 isone example of communication media. Communication media may typically beembodied by computer readable instructions, data structures, programmodules, or other data in a modulated data signal, such as a carrierwave or other transport mechanism, and includes any information deliverymedia. The term “modulated data signal” may describe a signal that hasone or more characteristics set or changed in such a manner as to encodeinformation in the signal. By way of example, and not limitation,communication media may include wired media such as a wired network ordirect-wired connection, and wireless media such as acoustic, radiofrequency (RF), infrared, and other wireless media. The term computerreadable media as used herein may include both storage media andcommunication media.

As stated above, a number of program modules and data files may bestored in system memory 1004, including operating system 1005. Whileexecuting on processing unit 1002 or secure processing unit fordecryption 1020, programming modules 1006 may perform processesincluding, for example, one or more method 500's stages as describedabove. The aforementioned process is an example; processing unit 1002and secure processing unit for decryption 1020 may perform otherprocesses.

Generally, consistent with per-subscriber stream management according toembodiments of this invention, program modules may include routines,programs, components, data structures, and other types of structuresthat may perform particular tasks or that may implement particularabstract data types. Moreover, embodiments may be practiced with othercomputer system configurations, including hand-held devices,multiprocessor systems, microprocessor-based or programmable consumerelectronics, minicomputers, mainframe computers, and the like.Embodiments of per-subscriber stream management may also be practiced indistributed network environments where tasks are performed by remoteprocessing devices that are linked through a communications network. Ina distributed network environment, program modules may be located inboth local and remote memory storage devices.

Furthermore, embodiments of per-subscriber stream management may bepracticed in an electrical circuit comprising discrete electronicelements, packaged or integrated electronic chips containing logicgates, a circuit utilizing a microprocessor, or on a single chipcontaining electronic elements or microprocessors. Embodiments may alsobe practiced using other technologies capable of performing logicaloperations such as, for example, AND, OR, and NOT, including but notlimited to mechanical, optical, fluidic, and quantum technologies. Inaddition, embodiments of the invention may be practiced within a generalpurpose computer or in any other circuits or systems.

Embodiments of per-subscriber stream management, for example, may beimplemented as a computer process (method), a network system, or as anarticle of manufacture, such as a computer program product or computerreadable media. The computer program product may be a computer storagemedia readable by a computer system and encoding a computer program ofinstructions for executing a computer process. The computer programproduct may also be a propagated signal on a carrier readable by anetwork system and encoding a computer program of instructions forexecuting a computer process. Accordingly, aspects of per-subscriberstream management may be embodied in hardware and/or in software(including firmware, resident software, micro-code, etc.). In otherwords, embodiments of per-subscriber stream management control may takethe form of a computer program product on a computer-usable orcomputer-readable storage medium having computer-usable orcomputer-readable program code embodied in the medium for use by or inconnection with an instruction execution system. A computer-usable orcomputer-readable medium may be any medium that can contain, store,communicate, propagate, or transport the program for use by or inconnection with the instruction execution system, apparatus, or device.

The computer-usable or computer-readable medium may be, for example butnot limited to, an electronic, magnetic, optical, electromagnetic,infrared, or semiconductor system, apparatus, device, or propagationmedium. More specific computer-readable medium examples (anon-exhaustive list), the computer-readable medium may include thefollowing: an electrical connection having one or more wires, a portablecomputer diskette, a random access memory (RAM), a read-only memory(ROM), an erasable programmable read-only memory (EPROM or Flashmemory), an optical fiber, and a portable compact disc read-only memory(CD-ROM). Note that the computer-usable or computer-readable mediumcould even be paper or another suitable medium upon which the program isprinted, as the program can be electronically captured, via, forinstance, optical scanning of the paper or other medium, then compiled,interpreted, or otherwise processed in a suitable manner, if necessary,and then stored in a computer memory.

Embodiments of per-subscriber stream management, for example, aredescribed above with reference to block diagrams and/or operationalillustrations of methods, systems, and computer program productsaccording to embodiments of per-subscriber stream management. Thefunctions/acts noted in the blocks may occur out of the order as shownin any flowchart. For example, two blocks shown in succession may infact be executed substantially concurrently or the blocks may sometimesbe executed in the reverse order, depending upon the functionality/actsinvolved.

While certain embodiments of per-subscriber stream management have beendescribed, other embodiments may exist. Furthermore, althoughembodiments have been described as being associated with data stored inmemory and other storage mediums, data can also be stored on or readfrom other types of computer-readable media, such as secondary storagedevices, like hard disks, floppy disks, or a CD-ROM, a carrier wave fromthe Internet, or other forms of RAM or ROM. Further, the disclosedmethods' stages may be modified in any manner, including by reorderingstages and/or inserting or deleting stages, without departing from theinvention.

While the specification includes examples, the invention's scope isindicated by the following claims. Furthermore, while the specificationhas been described in language specific to structural features and/ormethodological acts, the claims are not limited to the features or actsdescribed above. Rather, the specific features and acts described aboveare disclosed as example for embodiments of per-subscriber streammanagement.

We claim:
 1. A method comprising: establishing a unique state associatedwith a subscriber requesting a first asset, wherein the state isdifferent than the state for a second subscriber requesting the sameasset, wherein each unique state comprises a different reference pointinto the same asset; receiving an updated state specific to thesubscriber, the updated state comprising at least information sufficientto dynamically update a playlist based on a finite set of segmentsdeemed reasonable to collect, buffer, and render by the subscriber; andproviding the subscriber with the dynamically updated playlistcontaining a subset of the entirety of the sequence of stream segmentsbased on the received state.
 2. The method of claim 1, wherein thereceived state comprises information regarding a finite lifetime for theupdated playlist.
 3. The method of claim 1, wherein the received statecomprises information regarding a threshold for decommissioningresources.
 4. The method of claim 1, wherein the received state is arepresentation of the subscriber's activity.
 5. The method of claim 1,wherein the received state is created by a video application server. 6.The method of claim 5, wherein the received state comprises at least thelast segment of the first asset received by the subscriber.
 7. Themethod of claim 1, further comprising: posting the received state to asubscriber database in response to detecting that a buffer associatedwith the subscriber has been depleted.
 8. A method comprising: creatinga subscriber state unique to a subscriber requesting a selection of afirst video asset wherein each unique subscriber state comprises adifferent reference point into the first video asset; providing thesubscriber with a dynamically built playlist containing a subset of theentirety of segments associated with the video asset atsubscriber-eligible bit rates as determined by the subscriber state;receiving an updated subscriber state specific to the requestingsubscriber; and providing the subscriber with a dynamically updatedplaylist containing a subset of the entirety of segments based on thestate specific to the requesting subscriber.
 9. The method of claim 8,further comprising transmitting a message to indicate a successfulupdating of the subscriber state.
 10. The method of claim 8, furthercomprising transmitting a message to post the subscriber state to asubscriber database upon reaching an end of stream marker in the firstvideo asset.
 11. The method of claim 10, further comprising transmittingthe subscriber state to a video application server.
 12. The method ofclaim 8, further comprising performing local advertisement insertionfunctions based on the subscriber state.
 13. The method of claim 11,further comprising removing the subscriber state from the videoapplication server after completion of rendering the first video asset.14. The method of claim 8, further comprising employing the subscriberstate to manage quality of service on a per-subscriber basis.
 15. Asystem comprising: a client capable of receiving a playlist containing asubset of segments associated with a video asset; a video applicationserver to: request unique subscriber state information and to buildstate representations in a subscriber database on a per-subscriberbasis; receive an updated state specific to a first subscriber; andprovide the first subscriber with a dynamically updated playlistcontaining a subset of the entirety of the segments based on thereceived state.
 16. The system of claim 15, wherein the subscriberdatabase creates a representative bookmark for how much of the videoasset has been rendered by the client.
 17. The system of claim 15,wherein the subscriber database responds with a message indicatingsuccessful update of the subscriber state.
 18. The system of claim 15,wherein the video application server is further configured to parse theupdated playlist and build a list structure for the subscriber.
 19. Thesystem of claim 17, wherein the subscriber database determines whichvideo assets the subscriber is allowed to view.
 20. The system of claim19, wherein the subscriber database provides the client with a list ofviewable assets associated with a first service package.